ZKEA

Emerging Diseases : Biological Terrorism : Biological Warfare

Science & Technology

Through millennia of observation and trial-and-error, many early societies evolved mechanisms for managing disease. The explanations for these customs were generally obscured by taboo or supernatural explanation. Even so, these practices could sometimes be beneficial.

Perhaps the most widespread of these was the notion of quarantine. Many diseases were obviously contagious and so isolation of the diseased individual was often practiced. Those diseases that were particularly repellant or inspired the most fear, such as leprosy and rabies, were the ones most likely to force such a quarantine. In addition to stopping the further spread of disease, some societies had at their disposal a variety of medicinal plants and fungi. The biological basis for their effectiveness of such natural cures was of course unknown, but that did not prevent their adoption. Keen observation and experimentation could accomplish a great deal, even in the absence of a scientific conceptual framework.

Many early human groups also evolved reasonably effective sanitation customs. For example, even when nomadic tribes could remain in an area for a long time - say due to an unusually stable and rich food source - it was generally custom that camp would be moved every few weeks. This prevented an undue build up of human waste and garbage in the living vicinity, effectively eliminating a major health risk. Similar taboos prevented people from venturing into malarial swamps and lowlands, or handling the possibly diseased carcasses of certain dead animals. These customs and taboos, built up through time, acted as automatic barriers to disease acquisition and propagation.

In a few early cultures some sophisticated medical traditions developed. Probably the premier example here was the Ayurvedic medical system of ancient (and modern) India. Ayurvedic medicine anticipated many concepts once thought original to western medicine. Among other things, these included a germ theory of disease, an accurate model of the human circulatory system and an extensive system for surgical procedures. Ayurvedic medicine also codified the use of herbal preparations for the treatment of disease. To this end almost 300 species of plants were brought into service. Amusingly, marijuana (Cannabis) was one of these plants and was held in particularly high regard. It was successfully used to treat a long list of maladies.

Ayurvedic medicine aside, the growth of human populations soon inflicted a great cost to human health and happiness. As cities developed mankind was faced with a new high-density environment. In such urban environments there was no systematic science of sanitation, nor was there usually an appreciation of the underlying mechanisms of disease and epidemic. In addition, new diseases continued to adapt themselves to mankind, finding a fertile ecology in this suddenly-populous mammal. Finally, "civilized" diets were often much worse than that of primitive hunting groups, thus leading to an overall decline in health and immunity. (Judging from ancient skeletons, Paleolithic man was taller and more robust than his settled agricultural descendants. Civilization, built on agriculture, generated high populations but wasn't necessarily healthy for the individual). Therefore as populations slowly rose, mankind faced the triple perils of increased disease variety, increased disease opportunity, and decline in disease resistance.

This situation lasted for centuries, imposing extreme mortality rates upon urban populations. Indeed, until the 19th century, most cites were population sinks: more people died in cities than were born. Only the continued immigration of population from the relatively healthy countryside, driven by urban opportunity, kept city's populations from declining. When this demographic shift from the countryside stopped, due to whatever cause, entire cities could and did vanish. For example, Constantinople - which was perhaps the largest city in the world between the 8th and 11th century, was virtually deserted by the 14th. Cut off from its Anatolian agricultural heartland by the invading Turks, and decimated by repeated epidemics, the city depopulated itself within a few decades. Over the centuries similar demographic implosions struck countless other ancient cities. Only in very modern times has man had the notion that cities invariably increase in population.

Gradually this situation changed as the scientific framework began to make progress on disease. The first milestones were in sanitation. In 1854 John Snow discovered the reason for the spread of cholera, demonstrating its link to polluted London water supplies. Energetic reformers, such as Sir Edwin Chadwick, popularized broader measures to ensure sanitation throughout urban areas, leading to the landmark UK Sanitary Act of 1866. These innovations spread quickly worldwide, becoming standard practice by the 20th century. Today we take basic urban sanitation practices for granted. But they are in fact quite recent, and responsible for saving untold millions of lives over the past couple centuries.

In parallel, great progress was made in understanding the mechanisms of transmission. In 1796, Edward Jenner demonstrated the first modern system of vaccination. By 1801 almost 100,000 individuals were vaccinated against smallpox in the UK. In 1847 Ignal Semmelweiss observed that patients of physicians who performed autopsies suffered from a higher rate of infections than patients of midwives - who did not perform autopsies. In 1857, Louis Paster first noted that microorganisms were responsible for fermentation and putrefaction. Over time this led to the Germ Theory of Disease, first advanced by Robert Koch in 1876.

Moving into the 20th century the distinction between viruses and bacteria was elucidated, and for the first time, the specific organisms underlying specific diseases were discovered. Once these were determined, researchers began to test various compounds that killed these organisms. Thus, in 1905 Paul Ehrlich systematically tested compounds to kill the recently-discovered bacteria that causes Syphilis. Salvarsan, an arsenic compound, turned out to be effective, becoming the first of a series of such compounds. Although not always effective and given to a host of unpleasant side-effects, these compounds were far better than any previous treatments.

The 1940s saw the adoption of penicillin, the first true mass-produced antibiotic. Within a few years a number of other antibiotic compounds came to market. The effectiveness of these against various bacterial infections was stunning. For the first time in history, mankind had the means to effectively deal with a wide range of diseases. The event of mass vaccination, particularly for childhood diseases, brought another source of ancient terror under control. Optimism soared that a new age of medicine had dawned, in which all infectious disease would be vanquished.

Even at this early date, however, some scientists noted that microorganisms were developing resistance to these new antibiotics. As Darwin would have predicted, evolution already was reacting to these new environmental pressures, selecting for microorganisms that could resist these drugs.

In 1953, Watson and Crick published their seminal paper on the structure of DNA. This was the key catalyst that propelled a series of discoveries over the coming decades, at ever-increasing velocity. These included the first DNA cloning in 1972, the perfection of DNA sequencing in 1975, the discovery of the first human gene in 1977 and by 1987 the use of the first genetically-engineered microorganism in field trials.

Biotechnology was just getting started. The 1990's witnessed an absolute revolution in genetic engineering applications. The accomplishments were myriad. Among other things, scores of genetically-engineered insects, plants and animals were produced and commercialized. Computerized genetic scanning machines sequenced the complete genomes of several species - including humans. Transgenic organisms (those which have genes from another species spliced into their genome) became commonplace. For example, researchers spliced spider genes into goats, and then harvested spider silk from the transgenic goats milk. The possibilities were, indeed, endless.

But there was a dark aspect, and in the 1990's quiet but urgent voices began to speak about it. It has always been the case, throughout human history, that any technology can be put to both positive and negative uses. And these uses, positive or negative, are only limited by the strength of the technology itself. Biotechnology promised to be greatest and most pervasive invention since fire. If put to sinister uses, what were the ramifications? Had mankind finally crossed a fatal threshold, attaining technological prowess beyond his wisdom to control?

The outline of these elemental threats became increasingly clear as the century closed. Among other things, the genetic and biochemical basis for pathogenesis was now clear. In other words, the precise mechanisms that made some bacteria and viruses deadly became understood. These mechanisms could be - and were - manipulated and improved. In addition, it was now possible to create transgenic pathogens that combined optimal characteristics of multiple organisms. In theory, at least, one could combine infectiousness of the common cold and the potency of ebola. Further, the technology to execute on these threats was already worldwide, found in countless labs across the globe. Unlike nuclear energy, biotechnology did not require great expenditures of capital or personnel. It could thus be easily hidden, it could be done cheaply. A number of countries had already discovered this deadly calculus. By the 1980's massive germ-warfare efforts were underway in the Soviet Union. Over the following years these efforts dispersed to countless other countries.

Even when the intent was not hostile, basic experiments kept turning up discoveries with immediate and potentially apocalyptic implications. For instance, in 1999, researchers in Australia were attempting to discover better contraception drugs for mice. As part of their research they made a simple genetic alteration to the mousepox virus. To their astonishment, the altered virus turned out to be a killer - destroying 100% of all mice, even those that were vaccinated against it. Could the same experiment be done on a human virus, such as the closely-related smallpox? It appeared so.

And so we enter a new century, armed with powers beyond the imagination of previous generations. Where will this take us?

Archive Keys

Artificial Organisms, Synthetic Viruses, Oligomers

Australian Experiment, MousePox, SmallPox, Common Cold, Virulence

Bioethics, Bioterror, Restricting Research, Censoring, Health Policy

Chimeric Organisms, Chimera